Biracial Differences in Physical Activity and Body Composition Among Women

Abstract

TUTEN, CHRIS, RICHARD PETOSA, ROGER SARGENT AND ANNE WESTON. Biracial differences in physical activity and body composition among women. Obes Res. 1995;3:313-318. Overweight among black females is almost two times as frequent as among white females. Genetics, caloric intake, and physical activity have been identified as possible explanatory factors. This study assessed the differences in physical activity and body composition in 76 white and 66 black adult females. Black women had significantly higher (p=.OOOl) percent body fat (32.2 f 7.1) than white women (27.7 k 6.5) with a similar difference in weight (4.4 kg) approaching significance (p=.055). Physical activity was assessed using a structured 24-hour recall instrument. A purposive sampling design was implemented to control for age, education and occupation. A summary physical activity value unit for the 24-hour period revealed a significantly greater mean value for white females (41.93 + 4.7) than for black females (40.01 k 3.9) suggesting white females were more physically active (p=.02) although this was not a function of biracial differences in playhecreation and exerciselsport type of activities. Although both black and white females were found to be sedentary (MET value 5 2 ) over 90 percent of the time, black women were significantly more sedentary (p=.03). Biracial differences in discretionary non-exercise oriented activities may contribute to different rates of overweight observed between black and white women.

Ethnic differences in dietary intakes, physical activity, and energy expenditure in middle-aged, premenopausal women: the Healthy Transitions Study

“…With the use of a physical-activity-recall instrument, Tuten et al (20) found that white women had a greater mean physical activity in the previous 24-h time frame than did black women and that black women were significantly more sedentary. Additionally, 2 studies that used the doubly labeled water method (21,22) showed that total daily EE was significantly lower in African American women than in white women, mainly because the African American women had lower physical-activity EEs.…”

An "ecological" approach to the obesity pandemic

“…Fat loss and maintenance of lower equilibrium fat stores also becomes more difficult with age 26. Finally, there is increasing evidence of racial influences on energy balance 27. These biological influences explain much of the variance in body fat in individuals within a given environment, but they do not explain the large population increases which represent the epidemic itself.…”

Frequent Sequence Variation in the Human Myostatin (GDF8) Gene as a Marker for Analysis of Muscle-Related Phenotypes

“…This racial difference may be due to the greater muscle mass (Aloia et al, 1997;Cohn et al, 1977;and Gasperino et al, 1995) and the higher density of the lean body mass component of body composition (Schutte et al, 1984) found in African Americans. These differences are observed despite lower levels of physical activity among African Americans (Tuten et al, 1995). Therefore, it has been suggested that the racial differences in body composition may be due to a greater extent to heritable factors than they are to environment (Oritz et al, 1992).…”